Continued weakness in Apple (NASDAQ:AAPL) weighed heavily on the markets Tuesday, though better-than-expected news on the retail front was able to keep two of the three major indices in the black for the day.

The Dow Jones Industrial Average edged 0.2% higher to 13,534.89, and the S&P 500 finished up 0.11% to 1,472.34. But the AAPL-laden Nasdaq declined 0.22% to end at 3,110.78.

Apple’s stock dropped below $500 for the second time in as many days, and this time it stayed there — AAPL fell more than 3% to $485.31 on continued worries about slowing demand and margins for the iPhone 5, as well as lowered profit estimates by Nomura. Apple stock had not closed below $500 since February 2012.

Facebook (NASDAQ:FB) made its major announcement: The debut of a social search feature named “Graph Search” that allows users to search their own network of connections for people, places, photos and interests they share with others on the site. FB investors yawned, however, knocking shares down 2%. However, Yelp (NYSE:YELP) investors seemed convinced Graph Search could be trouble, bidding the business listings site down 7%.

Dell (NASDAQ:DELL) extended Monday’s rally with another 7% gain as rumors continue to fly that the company is considering a buyout. DELL is up 21% in the past two days.

Express (NYSE:EXPR) stole the show in the retail sector with a 23% surge after announcing surprisingly good holiday sales and raising its Q4 and full-year earnings forecasts. Other retailers headed higher were Aeropostale (NYSE:ARO, +7.6%), American Eagle (NYSE:AEO, +4.8%), Gap (NYSE:GPS, +3.4%) and Macy’s (NYSE:M, +2.2%) on the day’s broader sector news.

However, athletic apparel stock Lululemon (NASDAQ:LULU) didn’t share in the good news, dropping nearly 4% on Q4 revenue estimates that were lower than Street expectations.